Conventional fireplace simulator structures are divided into two types by the simulation of the burning substance of the fireplace. One is a simulation of burning flame by projecting varying light onto an image screen with imaging operation. Such as the flame simulator of electric fireplace disclosed in the patent with publication date Sep. 5, 2007 and publication number CN 200944291, comprises a light source, a flame board, a translucent image screen, a light shade with a transparent hole, a simulative fuel bed in front of a housing chamber. The light shade with a transparent hole is disposed at the back of the flame board, and a glass screen is fixed in front of the image screen. The light source cooperates with the light shade, and the light shade cooperates with a transmission mechanism. In the structure described above, the light shade can be disposed either horizontally or vertically to cooperate with the transmission mechanism to achieve a kind of axial and radial move of the light. The light forms the shape of flame after passing through a flame hole disposed on the flame board, and then be projected onto the image screen and the glass screen to carry out the visual effect of flame with vertical rising and horizontal waving. The other one is a simulation of burning charcoal flame in the fireplace by disposing an unchangeable structure with wood-like or charcoal-like figure besides or under the lower portion of the image screen. Such as the artificial wood for electric fireplace disclosed in the patent with publication date Apr. 7, 2004 and publication number CN 2610233, comprises an artificial wood base and a light source. The base is an irregular transparent chamber with artificial wood figure. LED tubes or light bulbs are disposed in the chamber. Each LED tubes or light bulbs are connected in series or in parallel and then lead out of the base by a conducting wire to connect with an external power source. The artificial wood base is of translucent material with pigment layers disposed irregularly on the external surface. The pigment layers can be chosen from various colors according to simulation needs, ordinarily, the dark brown similar to the wood color. The patent described above combines the artificial wood base and the light source. The light source is disposed in the artificial wood base. The base with pigment layer irregularly smeared on the external surface is made of transparent material. Thus, when the light source inside generates light, a kind of artificial burning effect with light and shade stager with each other is achieved, which is similar to the effect of burning charcoals. The structure is simple, realistic, and the figure and realism of which is closely to the natural burning flame. As to the charcoal flame simulated through the similar mode such as the wood or charcoal bed with fixed structure, the change between shade and light of the flame color achieves mainly via the pigment layers smeared irregularly on the external surface of the wood or the charcoal bed. Thus, the figure and the change between light and shade of the charcoal flame of each fireplace are constant and do not change. Thereby, the uniform external figure of the charcoal flame affects the visual effect. In addition, the brightness of the fireplace charcoal flame does not change either. The lack of intermittent light and shade of the spark light-spot and the realism make the simulation effect affected.